clutch fork free play

[aaalbedo]

I have an interesting issue with my 84. It was driving fine until suddenly the clutch would not disengage with a fully depressed pedal. Accelerated and shifted just fine through third gear, but would not disengage as I approached the next light. I've read through a lot of threads on the topic and none of the typical issues seem to apply.

Several years ago after breaking 3 cables in short order, a machinist friend converted me over to a nice heavily gusseted bearing assembly at the pedal end, and the pedal still checks out fine. So I thought the cable housing had pulled through the firewall, but that also remains nice and solid. Next thought was that the throwout bearing fork clip on the ball mount had broken, but the fork seems properly engaged on the ball. The cable attachment at the transmission end was fine, ball nut and lock nut properly assembled. I adjusted the cable shorter by a full inch, moving the ball nut pretty much up to the limit of the cable end threads, but it still will not disengage with full pedal travel. After adjusting the cable, if I start the engine in neutral, depress the pedal all the way and push the shifter towards first, the synchro nudges the car forward but there's no grinding of gears so it is not even close to disengaged.

So I removed the cable and spring from the throwout bearing fork, and took this video moving the fork by hand. It seems like there is normal top to bottom play at the beginning of the video, and the front to back movement seems consistent with the fork being properly engaged on the ball. But the front to back free play seems grossly excessive; where the cable attaches it moves freely by hand nearly two inches from the "rest" position before the throwout bearing engages the diaphragm spring, leaving less than half an inch more travel before the fork would hit the front of the aperture in the bell housing.

https://www.youtube.com/watch?v=JP2Sk2r ... e=youtu.be

So it's like either some spacer disappeared off the front of the throwout bearing, or the diaphragm spring fingers have collapsed. I think the latter happens gradually as the clutch disc thins, but it would be a gradual problem starting with partial disengagement issues, rather than this sudden >1" change in travel.

Any thoughts? I've put less than 5,000 miles on the car since I bought it, and PO claimed to have installed a "brand new clutch", but I have discovered a lot of other claims of mechanical work that turned out to be big fat lies.

Is there a way to inspect the clutch disc thickness without further disassembly? I don't relish the thought of trying to remove the transmission with my giant gorilla hands.

Larry

[vandor]

Broken or bent clutch fork?

[aaalbedo]

Not as far as I can tell, Csaba, but a good bet that it is bent. The throwout bearing moves freely on the shaft, and the fork seems straight but I didn't check carefully for that. I would think the bearing would bind if the fork was bent enough to displace it this far. I'll have to take a closer look but I'm out of town for the week. Thanks for your input.

Larry

[aaalbedo]

Yup, fork broken on both sides but enough steel left that it springs back to straight without pedal pressure so it looked OK. I wasn't too happy pulling the transmission without being sure what the problem was, but it really couldn't have been anything else.

Throwout seems to be seized solid, but wasn't making any noise. A greasy mess though.

Watch for an order this week, Csaba. Thanks for your help as always!

Larry